Clinker pushing device for shaft furnaces



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CLINKER PUSHING DEVICE 1 6R SHAFT FURNACES This invention relates to shaft furnace construction, and more particularly to means Within a furnace of this type adapted for removing from the bottom of the shaft clinkers accumulating therein.

In a furnace of the type referred to, the fuel is consumed in a vertically extending shaft, at the lower end of said shaft. To support combustion, air is introduced at one side of the combustion area, passing transversely of said area in a horizontal direction to the opposite side, with the hot products of combustion flowing through a bank of convection heating elements generally consisting of an array of vertically extending pipes, the air and the products of combustion then passing out of the furnace into a fine.

conventionally, means mounted below said combustion space is slidable horizontally across the shaft for the purpose of pushing out the shaft accumulated ashes, clinkers, and other residues after combustion of the fuel has taken place. It has been found, in this connection, that an undesirably great amount of driving force must be embodied in the horizontally slidable pusher means, with said force being applied to pushing members which must necessarily be of great weight. The high driving force and the correspondingly great weight of the pushing members are needed in view of the fact that the high temperature within the shaft, and the downward pressure exerted upon the clinkers by the column of coal gravitating within the shaft, causes compression of the cinders and other residues into a large clinker cake which can only be removed by application of a heavy force thereto.

In view of the difficulties which have heretofore existed, it is one important object of the present invention to reduce measurably the weight of the clinker removal means, and the amount of driving force which must be applied thereto. In carrying out this object, it is proposed to utilize a rotatable structure rather than a horizontally slidable one. it is further proposed that this structure include a plurality of spaced, sector-shaped, fiat bodies all secured fixedly to a single rotatable shaft and rotating in parallel planes against the accumulation of clinkers, in a manner to break up the clinker cake and shift the resultant pieces transversely out of the shaft.

It is further proposed, in carrying out the invention, to facilitate breaking up and movement of the clinkers accumulating at the bottom of the shaft in a manner that will improve the combustion, it being known that in the front part of the shaft, a stronger combustion takes place and therefore, correspondingly, a greater clinker accumulation. In accordance with the invention, the clinkers are broken up and shifted into this area, for further combustion of unburnt fuels previously encased therein, with the broken-up clinkers being disposed in the path of air moving into the shaft for the purpose of supporting combustion.

It is a further important object to so design a clinker removal means of the type referred to as to facilitate adjustment of the clinker removal operation according to the quantity of clinkers. In other words, while hereto- 2,804,850 Patented Sept. 3, 1957 fore it has been found feasible to operate the horizonsector-shaped bodies as to normally dispose said bodies in retracted position, away from the heat developed within the combustion space, thus to prevent distortion of the clinker removal means under the effects of an excessive amount of heat.

It is further proposed, in at least one form of the invention, to cause the sector-shaped bodies to be rotatably shifted through spaces between adjacent cooling pipes through which water is circulated, with said cooling pipes .and normally retracted bodies serving as a grate for the clinkers and other residues, the arrangement being such as to facilitate breakage of the clinkers by a co-operating action between the cooling pipes and the sector-shaped bodies.

Other objects and advantages will be apparent fromthe following detailed description, taken in conjunction with the accompanying drawing, wherein like reference numerals designate like parts throughout the several views, and wherein:

Pig. 1 is a vertical sectional view through a furnace in which is embodied a clinker removal device formed in accordance with the present invention, said device being shown in normal, retracted position in full lines and in extended, clinker-removing position in dotted lines,

Fig. 2 is a sectional view on line 2-2 of Fig. 1.

In the form of the invention shown in Figs. 1 and 2, the furnace has been designated generally at 46, and has a group of front cooling tubes 48 and a group of rear cooling tubes 50, at opposite sides of the shaft 52. In this form of the invention an auxiliary combustion chamber has been designated at 54, the hot products of combustion leaving the furnace through said auxiliary chamher to pass through the spaces between convection pipes 39.

Formed in the furnace bottom is a transversely extending, arcuately shaped recess 56, and extending transversely of the furnace just above said recess is a shaft element 5%. A series of cooling tubes 6%) is provided, said tubes being connected at one end in communication with a transversely disposed m-ain cooling tube 62, and being connected at their other ends in communication with the water jacket of the furnace. Tubes extend approximately horizontally at their front ends, shown at the left in Fig. 1, the horizontal portions of said tubes merging into upwardly curving portions that are connected in communication with the furnace water jacket. The tubes are spaced transversely of the furnace, extending across the recess 56, immediately above the shaft element 58.

The clinker removal plates in this form have been designated at 64, and are of approximately semicircular outer configuration, said plates being attached to the shaft element 58 for rotation therewith between the normally retracted, full line positions and the extended, dotted line positions shown in Fig. 1. Plates 64 are thus normally disposed within recess 56, the upper edges of the plates extending within the spaces between the upwardly curving rear portions of the tubes 60 to cooperate with these portions of tubes in providing a grate at the bottom of shaft 52. The edges of plates 64 that are interposed between the curved parts of tubes 60 are curved correspondingly to said parts of the tubes.

' 3 when clinkers are to be broken up and removed, a handle 40 wouldbeswung, to rotate shaft element 58 in a counterclockwise direction, thus causing plates 64 to be partially extended out of recess 56 in the dotted line position of Eig l, This causesthev accumulated clinkers to be broken' upand shifted-to the left. out of the bottom of, the shaft 52.;

' Inthis arrangement, clinkers might tend to fall. into. the recess 56 when the plates 64 are shifted; to their dotted line pos ions- Accordingly, on the trailing ends of the [plates 64 there, are formed enlargements 66; which substantially close the spaces between the plates andin effect wipe over, the. bottom of the recess 56. As a rewhen. the plates are, returned from their dotted to. their full. line, positions, the enlargements will push out;

of; e receissllany'small pieces of clinkerstthat may have dipped h Y i In this arrangement, the use of the cooling tubes 60, alternating with thevclinker removal plates '64; not only sei yes' tokeep the plates 64cool, to prevent warping: or

iz heplates' '6 .4..

' It will be' apparent to those skilled in the art that many rtion thereof; but also acts upon. the clinker cake in such a manner asto condition the same for breakage plane of said front wall and with its rearward end the major distance between the planes of said wal fi said front wall terminating in spaced relation to said grate, a horizontal shaft element substantially in the plane of said front wall below the top surface of said grate and rotatable between two end positions, a plurality of platelike, substantially segment-shaped bodies spaced from each other and secured to said element in planes at right angles thereto, each plate having a first, a second and a third edge, said first edge extending, in the first end position of said element, in close proximity of said; topsurface of said grate approximately as far as said rear end of said grate and, in the second position of said element, extending in a direction towards said frontwall, said second edge being substantially radial and located below said top surface-"inany position of said element, said third edge being arcuate and concentric with said shaft element and including lateral nose-like projections at the corner formed by said second and third edges, and said furnace shaft space having a; floor formed'with an r i s. s m l ment n -fi .c rv t r of i hi d,

edge and into which said projections extend to remove matter which may have fallen into said recess upon movement Drain element from itssecond into its first endv position.

RefereucesCitedin the file of this patent UNITED STATES PATENTS Germany June14, 1951 

